docs: Update references to workspace layout

Update all doc references from old paths to workspace structure:
- assets/demo.seq → workspaces/main/timeline.seq
- assets/music.track → workspaces/main/music.track
- assets/final/demo_assets.txt → workspaces/main/assets.txt
- assets/test_demo.* → workspaces/test/*

Files updated:
- HOWTO.md: Add workspace selection, update paths
- SEQUENCE.md: Update examples and integration
- ASSET_SYSTEM.md: Workspace-aware workflow
- CONTRIBUTING.md: Workspace timeline paths
- ARCHITECTURE.md: Generic workspace reference

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

1 files changed, 11 insertions, 9 deletions

diff --git a/doc/SEQUENCE.md b/doc/SEQUENCE.md
index 954c816..68bd129 100644
--- a/doc/SEQUENCE.md
+++ b/doc/SEQUENCE.md
@@ -7,7 +7,8 @@ This document describes the `.seq` file format used to define demo timelines.
 Sequence files (`.seq`) define the timeline and layering of visual effects. They are compiled by `seq_compiler` into C++ code at build time.
 
 **Locations:**
-- Demo sequence: `assets/demo.seq`
+- Main demo: `workspaces/main/timeline.seq`
+- Test demo: `workspaces/test/timeline.seq`
 - Compiler: `tools/seq_compiler.cc`
 - Generated output: `src/generated/timeline.cc`
 
@@ -158,18 +159,18 @@ SEQUENCE 0b 0
 
 **ASCII Chart (Terminal):**
 ```bash
-./build/seq_compiler assets/demo.seq --gantt=timeline.txt
+./build/seq_compiler workspaces/main/timeline.seq --gantt=timeline.txt
 ```
 
 **HTML/SVG Chart (Recommended):**
 ```bash
-./build/seq_compiler assets/demo.seq --gantt-html=timeline.html
+./build/seq_compiler workspaces/main/timeline.seq --gantt-html=timeline.html
 ```
 Interactive visualization with hover tooltips, color coding, and zoom/pan.
 
 ### Validation Only
 ```bash
-./build/seq_compiler assets/demo.seq
+./build/seq_compiler workspaces/main/timeline.seq
 ```
 Validates syntax without generating code.
 
@@ -177,13 +178,13 @@ Validates syntax without generating code.
 
 ## Integration
 
-CMake automatically invokes the compiler on `assets/demo.seq` changes:
+CMake automatically invokes the compiler on workspace timeline changes:
 
 ```cmake
 add_custom_command(
   OUTPUT ${GENERATED_DIR}/timeline.cc
-  COMMAND seq_compiler assets/demo.seq ${GENERATED_DIR}/timeline.cc
-  DEPENDS assets/demo.seq
+  COMMAND seq_compiler ${WORKSPACE_TIMELINE} ${GENERATED_DIR}/timeline.cc
+  DEPENDS ${WORKSPACE_TIMELINE}
 )
 ```
 
@@ -191,7 +192,8 @@ add_custom_command(
 
 ## See Also
 
-- `assets/demo.seq` - Current demo timeline
+- `workspaces/main/timeline.seq` - Main demo timeline
+- `workspaces/test/timeline.seq` - Test demo timeline
+- `doc/WORKSPACE_SYSTEM.md` - Workspace organization
 - `src/gpu/demo_effects.h` - Available effect classes
-- `doc/EFFECTS_CATALOG.md` - Detailed effect reference (if needed)
 - `doc/HOWTO.md` - Building and running